1. Field of the Invention
The present invention relates to a stage for a substrate on which is mounted a substrate such as a semiconductor wafer.
2. Description of the Related Art
Semiconductors that require ultrafine fabrication such as a MEMS (Micro Electro Mechanical System) or a thick film circuit board are manufactured utilizing photolithography techniques. When applying a photolithography technique such as exposure, development, or etching, a substrate is fixed on a stage and the photolithography technique is performed.
Japanese Patent Laid-Open No. 2001-160586 proposes a stage in which a peripheral section of the stage and a peripheral section of through holes for lift pins are caused to project more than another section, and the remaining section is configured as a concave portion. By allowing a coolant to flow to the concave portion, the stage can cool the substrate efficiently.
Further, Japanese Patent Laid-Open No. 2003-158160 discloses a device in which a hand delivers a substrate to a stage. The hand is provided with an annular suction surface at an outer circumferential section of a circular suction portion, and suction holes that connect to a vacuum chamber are formed in the suction surface.